Generally when things in the Bible are described as having two sides -- especially when the two sides are equal -- it has to do with a completeness and balance between the desire for good and the understanding of truth. These are the two elements of a spiritual life -- we have to determine that we wish to do what is right, and have to understand what that means and how to do it. When they are in balance and equivalent, we can grow closer to the Lord. See Exodus 25:12 as an example.

(References: Arcana Coelestia 9495, 9511, 9512, 9556)